Interleaving sense elements of a capacitive-sense array

ABSTRACT

Apparatuses and methods of sense arrays with interleaving sense elements are described. One capacitive-sense array includes a repeating pattern of conductive elements disposed along a first axis. The repeating pattern includes a first conductive element comprising a first polygon shape with a first width defined along a second axis that is perpendicular to the first axis and a second conductive element that is electrically coupled to and co-planar with the first conductive element. The second conductive element includes a second polygon shape with a second width defined along a third axis that is perpendicular to the first axis and parallel to the second axis. The repeating pattern also includes third and fourth conductive elements that are electrically coupled to and co-planar with the first and second conductive elements. The third conductive element includes the first shape and the fourth conductive element includes the second shape.

RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.14/098,057, filed Dec. 5, 2013, which claims the benefit of U.S.Provisional Application No. 61/875,863, filed Sep. 10, 2013 all of whichare incorporated by reference herein in their entirety.

TECHNICAL FIELD

The present disclosure relates generally to sensing systems, and moreparticularly to capacitance-sensing systems configurable to determinetouch locations of touches on the capacitive-sensing systems.

BACKGROUND

Capacitance sensing systems can sense electrical signals generated onelectrodes that reflect changes in capacitance. Such changes incapacitance can indicate a touch event (i.e., the proximity of an objectto particular electrodes). Capacitive sense elements may be used toreplace mechanical buttons, knobs and other similar mechanical userinterface controls. The use of a capacitive sense element allows for theelimination of complicated mechanical switches and buttons, providingreliable operation under harsh conditions. In addition, capacitive senseelements are widely used in modern customer applications, providing newuser interface options in existing products. Capacitive sense elementscan range from a single button to a large number arranged in the form ofa capacitive sense array for a touch-sensing surface.

Transparent touch screens that utilize capacitive sense arrays areubiquitous in today's industrial and consumer markets. They can be foundon cellular phones, GPS devices, set-top boxes, cameras, computerscreens, MP3 players, digital tablets, and the like. The capacitivesense arrays work by measuring the capacitance of a capacitive senseelement, and looking for a delta in capacitance indicating a touch orpresence of a conductive object. When a conductive object (e.g., afinger, hand, or other object) comes into contact or close proximitywith a capacitive sense element, the capacitance changes and theconductive object is detected. The capacitance changes of the capacitivetouch sense elements can be measured by an electrical circuit. Theelectrical circuit converts the measured capacitances of the capacitivesense elements into digital values.

There are two typical types of capacitance: 1) mutual capacitance wherethe capacitance-sensing circuit has access to both electrodes of thecapacitor; 2) self-capacitance where the capacitance-sensing circuit hasonly access to one electrode of the capacitor where the second electrodeis tied to a DC voltage level or is parasitically coupled to EarthGround. A touch panel has a distributed load of capacitance of bothtypes (1) and (2) and Cypress' touch solutions sense both capacitanceseither uniquely or in hybrid form with its various sense modes.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention is illustrated by way of example, and not oflimitation, in the figures of the accompanying drawings.

FIG. 1 is a block diagram illustrating an embodiment of an electronicsystem that processes touch data.

FIG. 2 is a block diagram illustrating an embodiment of an electronicsystem that processed touch data.

FIG. 3 illustrates an embodiment of a capacitive-sense array having asingle solid diamond (SSD) pattern.

FIG. 4 illustrates an embodiment of a capacitive-sense array having adouble solid diamond (DSD) pattern.

FIG. 5 illustrates a cross section view of three unit cells andcorresponding capacitance profiles of the capacitive-sense array of FIG.4 according to one embodiment.

FIG. 6 illustrates a cross section view of three unit cells andcorresponding capacitance profiles of the capacitive-sense array withinterleaving sense elements according to one embodiment.

FIG. 7 illustrates an embodiment of a capacitive-sense array having aDSD pattern with interleaving sense elements according to oneembodiment.

FIG. 8 is a waveform diagram illustrating a signal response of thecapacitive-sense array of FIG. 4 according to one embodiment.

FIG. 9 is a waveform diagram illustrating a signal response of thecapacitive-sense array of FIG. 7 according to one embodiment.

FIG. 10A illustrates a square swirl region according to one embodiment.

FIG. 10B illustrates a triangle swirl region according to oneembodiment.

FIG. 10C illustrates a sector swirl region according to one embodiment.

FIG. 11A illustrates a triangle swirl electrode used in an interleavingDSD pattern according to one embodiment.

FIG. 11B illustrates triangle swirl electrodes combined in aninterleaving DSD pattern according to one embodiment.

FIG. 12A illustrates a swirl electrode 1200 used in an interleaving DSDpattern according to one embodiment.

FIG. 12B illustrates another embroidered swirl electrodes used in aninterleaving DSD pattern according to another embodiment.

FIG. 13 illustrates a sector swirl electrodes used in an interleavingSSD pattern according to one embodiment.

FIG. 14 is a flow diagram of a method of sensing a capacitive-sensearray with interleaving sense electrodes according to an embodiment.

DETAILED DESCRIPTION

In the following description, for purposes of explanation, numerousspecific details are set forth in order to provide a thoroughunderstanding of the present invention. It will be evident, however, toone skilled in the art that the present invention may be practicedwithout these specific details. In other instances, well-known circuits,structures, and techniques are not shown in detail, but rather in ablock diagram in order to avoid unnecessarily obscuring an understandingof this description.

Reference in the description to “one embodiment” or “an embodiment”means that a particular feature, structure, or characteristic describedin connection with the embodiment is included in at least one embodimentof the invention. The phrase “in one embodiment” located in variousplaces in this description does not necessarily refer to the sameembodiment.

Apparatuses and methods of sense arrays with interleaving sense elementsare described. One capacitive-sense array includes a first electrode anda second electrode disposed adjacent to the first electrode in a firstaxis. The capacitive-sense array comprises a sensor pitch in the firstaxis. The first electrode includes a first sense element including afirst shape and a first interleaving sense element that interleaves witha first portion and a second portion of the second electrode to extend afirst dimension of the first electrode to be greater than the sensorpitch in the first axis. The second electrode includes a second senseelement including the first shape and a second interleaving senseelement that interleaves with a first portion and a second portion ofthe first electrode to extend a second dimension of the second electrodeto be greater than the sensor pitch in the first axis. In someembodiments, the first dimension is greater than the sensor pitch in thefirst axis by two or more. The embodiments described herein includedifferent shapes and patterns with interleaving sense elements.Embodiments of interleaving sense elements can be disposed so that adimension (width or height) of the electrode is more than the sensorpitch in that dimension. In some cases, the dimension is twice or morethan twice the sensor pitch in that dimension. In other embodiments, thedimension may be greater than the sensor pitch by other factors thantwo. The embodiments described herein are directed to specificgeometries, but other geometries of the shapes and patterns can beutilized. In some embodiments, the interleaving sense elements can beused in one dimension. In other embodiments, the interleaving senseelements can be used in multiple dimensions. Various embodiments of theinterleaving sense elements are described below with respect to FIGS.4-14.

FIG. 1 illustrates a block diagram of one embodiment of an electronicsystem 100 including a processing device 110 that may be configured tomeasure capacitances from a touch-sensing surface 116 including acapacitive-sense array 121. In one embodiment, a multiplexer circuit maybe used to connect a capacitive-sensing circuit 101 with a sense array121. The electronic system 100 includes a touch-sensing surface 116(e.g., a touchscreen, or a touch pad) coupled to the processing device110, which is coupled to a host 150. In one embodiment the touch-sensingsurface 116 is a two-dimensional sense array 121 that uses processingdevice 110 to detect touches on the surface 116.

In one embodiment, the sense array 121 includes electrodes 121(1)-121(N)(where N is a positive integer) that are disposed as a two-dimensionalmatrix (also referred to as an XY matrix). The sense array 121 iscoupled to pins 113(1)-113(N) of the processing device 110 via one ormore analog buses 115 transporting multiple signals. In an alternativeembodiment without an analog bus, each pin may instead be connectedeither to a circuit that generates a transmit (TX) signal or to anindividual receive (RX) sensor circuit. The capacitive sense array 121may include a multi-dimension capacitive sense array. Themulti-dimension sense array includes multiple sense elements, organizedas rows and columns. In another embodiment, the capacitive sense array121 operates as an all-points-addressable (“APA”) mutual capacitivesense array. In another embodiment, the capacitive sense array 121operates as a coupled-charge receiver. In another embodiment, thecapacitive sense array 121 is non-transparent capacitive sense array(e.g., PC touchpad). The capacitive sense array 121 may be disposed tohave a flat surface profile. Alternatively, the capacitive sense array121 may have non-flat surface profiles. Alternatively, otherconfigurations of capacitive sense arrays may be used. For example,instead of vertical columns and horizontal rows, the capacitive sensearray 121 may have a hexagon arrangement, or the like, as would beappreciated by one of ordinary skill in the art having the benefit ofthis disclosure. In one embodiment, the capacitive sense array 121 maybe included in an ITO panel or a touch screen panel.

In one embodiment, the capacitance-sensing circuit 101 may include arelaxation oscillator or other means to convert a capacitance into ameasured value. The capacitance-sensing circuit 101 may also include acounter or timer to measure the oscillator output. The processing device110 may further include software components to convert the count value(e.g., capacitance value) into a touch detection decision (also referredto as switch detection decision) or relative magnitude. It should benoted that there are various known methods for measuring capacitance,such as current versus voltage phase shift measurement,resistor-capacitor charge timing, capacitive bridge divider, chargetransfer, successive approximation, sigma-delta modulators,charge-accumulation circuits, field effect, mutual capacitance,frequency shift, or other capacitance measurement algorithms. It shouldbe noted however, instead of evaluating the raw counts relative to athreshold, the capacitance-sensing circuit 101 may be evaluating othermeasurements to determine the user interaction. For example, in thecapacitance-sensing circuit 101 having a sigma-delta modulator, thecapacitance-sensing circuit 101 is evaluating the ratio of pulse widthsof the output (i.e., density domain), instead of the raw counts beingover or under a certain threshold.

In another embodiment, the capacitance-sensing circuit 101 includes a TXsignal generator to generate a TX signal to be applied to the TXelectrode and a receiver (also referred to as a sensing channel), suchas an integrator, coupled to measure an RX signal on the RX electrode.In a further embodiment, the capacitance-sensing circuit includes ananalog-to-digital converter (ADC) coupled to an output of the receiverto convert the measured RX signal to a digital value (capacitancevalue). The digital value can be further processed by the processingdevice 110, the host 150 or both.

The processing device 110 is configured to detect one or more touches ona touch-sensing device, such as the capacitive sense array 121. Theprocessing device can detect conductive objects, such as touch objects140 (fingers or passive styluses, an active stylus, or any combinationthereof. The capacitance-sensing circuit 101 can measure touch data onthe capacitive sense array 121. The touch data may be represented asmultiple cells, each cell representing an intersection of sense elements(e.g., electrodes) of the capacitive sense array 121. The capacitivesense elements are electrodes of conductive material, such as copper.The sense elements may also be part of an ITO panel. The capacitivesense elements can be configurable to allow the capacitive-sensingcircuit 101 to measure self-capacitance, mutual capacitance, or anycombination thereof. In another embodiment, the touch data is a 2Dcapacitive image of the capacitive sense array 125. In one embodiment,when the capacitance-sensing circuit 101 measures mutual capacitance ofthe touch-sensing device (e.g., capacitive sense array 121), thecapacitance-sensing circuit 101 obtains a 2D capacitive image of thetouch-sensing device and processes the data for peaks and positionalinformation. In another embodiment, the processing device 110 is amicrocontroller that obtains a capacitance touch signal data set, suchas from a sense array, and finger detection firmware executing on themicrocontroller identifies data set areas that indicate touches, detectsand processes peaks, calculates the coordinates, or any combinationtherefore. The firmware identifies the peaks using the embodimentsdescribed herein. The firmware can calculate a precise coordinate forthe resulting peaks. In one embodiment, the firmware can calculate theprecise coordinates for the resulting peaks using a centroid algorithm,which calculates a centroid of the touch, the centroid being a center ofmass of the touch. The centroid may be an X/Y coordinate of the touch.Alternatively, other coordinate interpolation algorithms may be used todetermine the coordinates of the resulting peaks. The microcontrollercan report the precise coordinates to a host processor, as well as otherinformation.

In one embodiment, the processing device 110 further includes processinglogic 102. Operations of the processing logic 102 may be implemented infirmware; alternatively, they may be implemented in hardware orsoftware. The processing logic 102 may receive signals from thecapacitance-sensing circuit 101, and determine the state of the sensearray 121, such as whether an object (e.g., a finger) is detected on orin proximity to the sense array 121 (e.g., determining the presence ofthe object), resolve where the object is on the sense array (e.g.,determining the location of the object), tracking the motion of theobject, or other information related to an object detected at the touchsensor.

In another embodiment, instead of performing the operations of theprocessing logic 102 in the processing device 110, the processing device110 may send the raw data or partially-processed data to the host 150.The host 150, as illustrated in FIG. 1, may include decision logic 151that performs some or all of the operations of the processing logic 102.Operations of the decision logic 151 may be implemented in firmware,hardware, software, or a combination thereof. The host 150 may include ahigh-level Application Programming Interface (API) in applications 152that perform routines on the received data, such as compensating forsensitivity differences, other compensation algorithms, baseline updateroutines, start-up and/or initialization routines, interpolationoperations, or scaling operations. The operations described with respectto the processing logic 102 may be implemented in the decision logic151, the applications 152, or in other hardware, software, and/orfirmware external to the processing device 110. In some otherembodiments, the processing device 110 is the host 150.

In another embodiment, the processing device 110 may also include anon-sensing actions block 103. This block 103 may be used to processand/or receive/transmit data to and from the host 150. For example,additional components may be implemented to operate with the processingdevice 110 along with the sense array 121 (e.g., keyboard, keypad,mouse, trackball, LEDs, displays, or other peripheral devices).

As illustrated, capacitance-sensing circuit 101 may be integrated intoprocessing device 110. Capacitance-sensing circuit 101 may includeanalog I/O for coupling to an external component, such as touch-sensorpad (not shown), capacitive sense array 121, touch-sensor slider (notshown), touch-sensor buttons (not shown), and/or other devices. Thecapacitance-sensing circuit 101 may be configurable to measurecapacitance using mutual-capacitance sensing techniques,self-capacitance sensing technique, charge coupling techniques or thelike. In one embodiment, capacitance-sensing circuit 101 operates usinga charge accumulation circuit, a capacitance modulation circuit, orother capacitance sensing methods known by those skilled in the art. Inan embodiment, the capacitance-sensing circuit 101 is of the CypressTMA-3xx, TMA-4xx, or TMA-xx families of touch screen controllers.Alternatively, other capacitance-sensing circuits may be used. Themutual capacitive sense arrays, or touch screens, as described herein,may include a transparent, conductive sense array disposed on, in, orunder either a visual display itself (e.g. LCD monitor), or atransparent substrate in front of the display. In an embodiment, the TXand RX electrodes are configured in rows and columns, respectively. Itshould be noted that the rows and columns of electrodes can beconfigured as TX or RX electrodes by the capacitance-sensing circuit 101in any chosen combination. In one embodiment, the TX and RX electrodesof the sense array 125 are configurable to operate as a TX and RXelectrodes of a mutual capacitive sense array in a first mode to detecttouch objects, and to operate as electrodes of a coupled-charge receiverin a second mode to detect a stylus on the same electrodes of the sensearray. The stylus, which generates a stylus TX signal when activated, isused to couple charge to the capacitive sense array, instead ofmeasuring a mutual capacitance at an intersection of a RX electrode anda TX electrode (including one or more sense element) as done duringmutual-capacitance sensing. An intersection between two sense elementsmay be understood as a location at which one sense electrode crossesover or overlaps another, while maintaining galvanic isolation from eachother. The capacitance-sensing circuit 101 does not usemutual-capacitance or self-capacitance sensing to measure capacitancesof the sense elements when performing a stylus sensing. Rather, thecapacitance-sensing circuit 101 measures a charge that is capacitivelycoupled between the sense array 121 and the stylus as described herein.The capacitance associated with the intersection between a TX electrodeand an RX electrode can be sensed by selecting every availablecombination of TX electrode and RX electrode. When a touch object, suchas a finger or stylus, approaches the capacitive sense array 121, theobject causes a decrease in mutual capacitance between some of the TX/RXelectrodes. In another embodiment, the presence of a finger increasesthe coupling capacitance of the electrodes. Thus, the location of thefinger on the capacitive sense array 121 can be determined byidentifying the RX electrode having a decreased coupling capacitancebetween the RX electrode and the TX electrode to which the TX signal wasapplied at the time the decreased capacitance was measured on the RXelectrode. Therefore, by sequentially determining the capacitancesassociated with the intersection of electrodes, the locations of one ormore inputs can be determined. It should be noted that the process cancalibrate the sense elements (intersections of RX and TX electrodes) bydetermining baselines for the sense elements. It should also be notedthat interpolation may be used to detect finger position at betterresolutions than the row/column pitch as would be appreciated by one ofordinary skill in the art having the benefit of this disclosure. Inaddition, various types of coordinate interpolation algorithms may beused to detect the center of the touch as would be appreciated by one ofordinary skill in the art having the benefit of this disclosure.

It should also be noted that the embodiments described herein are notlimited to having a configuration of a processing device coupled to ahost, but may include a system that measures the capacitance on thesensing device and sends the raw data to a host computer where it isanalyzed by an application. In effect, the processing that is done byprocessing device 110 may also be done in the host.

The processing device 110 may reside on a common carrier substrate suchas, for example, an integrated circuit (IC) die substrate, or amulti-chip module substrate. Alternatively, the components of theprocessing device 110 may be one or more separate integrated circuitsand/or discrete components. In one embodiment, the processing device 110may be the Programmable System on a Chip (PSoC®) processing device,developed by Cypress Semiconductor Corporation, San Jose, Calif.Alternatively, the processing device 110 may be one or more otherprocessing devices known by those of ordinary skill in the art, such asa microprocessor or central processing unit, a controller,special-purpose processor, digital signal processor (DSP), anapplication specific integrated circuit (ASIC), a field programmablegate array (FPGA), or other programmable device. In an alternativeembodiment, for example, the processing device 110 may be a networkprocessor having multiple processors including a core unit and multiplemicro-engines. Additionally, the processing device 110 may include anycombination of general-purpose processing device(s) and special-purposeprocessing device(s).

Capacitance-sensing circuit 101 may be integrated into the IC of theprocessing device 110, or alternatively, in a separate IC.Alternatively, descriptions of capacitance-sensing circuit 101 may begenerated and compiled for incorporation into other integrated circuits.For example, behavioral level code describing the capacitance-sensingcircuit 101, or portions thereof, may be generated using a hardwaredescriptive language, such as VHDL or Verilog, and stored to amachine-accessible medium (e.g., CD-ROM, hard disk, floppy disk, etc.).Furthermore, the behavioral level code can be compiled into registertransfer level (“RTL”) code, a netlist, or even a circuit layout andstored to a machine-accessible medium. The behavioral level code, theRTL code, the netlist, and the circuit layout may represent variouslevels of abstraction to describe capacitance-sensing circuit 101.

It should be noted that the components of electronic system 100 mayinclude all the components described above. Alternatively, electronicsystem 100 may include some of the components described above.

In one embodiment, the electronic system 100 is used in a tabletcomputer. Alternatively, the electronic device may be used in otherapplications, such as a notebook computer, a mobile handset, a personaldata assistant (“PDA”), a keyboard, a television, a remote control, amonitor, a handheld multi-media device, a handheld media (audio and/orvideo) player, a handheld gaming device, a signature input device forpoint of sale transactions, an eBook reader, global position system(“GPS”) or a control panel. The embodiments described herein are notlimited to touch screens or touch-sensor pads for notebookimplementations, but can be used in other capacitive sensingimplementations, for example, the sensing device may be a touch-sensorslider (not shown) or touch-sensor buttons (e.g., capacitance sensingbuttons). In one embodiment, these sensing devices include one or morecapacitive sensors or other types of capacitance-sensing circuitry. Theoperations described herein are not limited to notebook pointeroperations, but can include other operations, such as lighting control(dimmer), volume control, graphic equalizer control, speed control, orother control operations requiring gradual or discrete adjustments. Itshould also be noted that these embodiments of capacitive sensingimplementations may be used in conjunction with non-capacitive sensingelements, including but not limited to pick buttons, sliders (ex.display brightness and contrast), scroll-wheels, multi-media control(ex. volume, track advance, etc.) handwriting recognition, and numerickeypad operation.

FIG. 2 is a block diagram illustrating one embodiment of sense array 121composed of orthogonal electrodes and a capacitance-sensing circuit 101that converts changes in measured capacitances to coordinates indicatingthe presence and location of touch. In one embodiment, thecapacitance-sensing circuit 101 may measure mutual capacitances forintersections between the transmit and receive electrodes in the sensearray 121. The touch coordinates are calculated based on changes in themeasured capacitances relative to the capacitances of the same touchsense array 121 in an un-touched state. In one embodiment, sense array121 and capacitance-sensing circuit 101 are implemented in a system suchas electronic system 100. Sense array 121 includes a matrix 225 of N×Melectrodes (N receive electrodes and M transmit electrodes), whichfurther includes transmit (TX) electrode 222 and receive (RX) electrode223. Each of the electrodes in matrix 225 is connected with capacitancesensing circuit 101 through demultiplexer 212 and multiplexer 213.

Capacitance-sensing circuit 101 includes multiplexer control 211,demultiplexer 212, multiplexer 213, clock generator 214, signalgenerator 215, demodulation circuit 216, and analog to digital converter(ADC) 217. ADC 217 is further coupled with touch coordinate converter218. Touch coordinate converter 218 may be implemented in the processinglogic 102.

The transmit and receive electrodes in the electrode matrix 225 may bearranged so that each of the transmit electrodes overlap and cross eachof the receive electrodes such as to form an array of intersections,while maintaining galvanic isolation from each other. Thus, eachtransmit electrode may be capacitively coupled with each of the receiveelectrodes. For example, transmit electrode 222 is capacitively coupledwith receive electrode 223 at the point where transmit electrode 222 andreceive electrode 223 overlap.

Clock generator 214 supplies a clock signal to signal generator 215,which produces a TX signal 224 to be supplied to the transmit electrodesof touch sense array 121. In one embodiment, the signal generator 215includes a set of switches that operate according to the clock signalfrom clock generator 214. The switches may generate a TX signal 224 byperiodically connecting the output of signal generator 215 to a firstvoltage and then to a second voltage, wherein said first and secondvoltages are different.

The output of signal generator 215 is connected with demultiplexer 212,which allows the TX signal 224 to be applied to any of the M transmitelectrodes of sense array 121. In one embodiment, multiplexer control211 controls demultiplexer 212 so that the TX signal 224 is applied toeach transmit electrode 222 in a controlled sequence. Demultiplexer 212may also be used to ground, float, or connect an alternate signal to theother transmit electrodes to which the TX signal 224 is not currentlybeing applied. In an alternate embodiment the TX signal 224 may bepresented in a true form to a subset of the transmit electrodes 222 andin complement form to a second subset of the transmit electrodes 222,wherein there is no overlap in members of the first and second subset oftransmit electrodes 222.

Because of the capacitive coupling between the transmit and receiveelectrodes, the TX signal 224 applied to each transmit electrode inducesa current within each of the receive electrodes. For instance, when theTX signal 224 is applied to transmit electrode 222 through demultiplexer212, the TX signal 224 induces an RX signal 227 on the receiveelectrodes in matrix 225. The RX signal 227 on each of the receiveelectrodes can then be measured in sequence by using multiplexer 213 toconnect each of the N receive electrodes to demodulation circuit 216 insequence.

The mutual capacitance associated with the intersections of all TXelectrodes and RX electrodes can be measured by selecting everyavailable combination of TX electrode and an RX electrode usingdemultiplexer 212 and multiplexer 213. To improve performance,multiplexer 213 may also be segmented to allow more than one of thereceive electrodes in matrix 225 to be routed to additional demodulationcircuits 216. In an optimized configuration, wherein there is a 1-to-1correspondence of instances of demodulation circuit 216 with receiveelectrodes, multiplexer 213 may not be present in the system.

When a conductive object, such as a finger, approaches the electrodematrix 225, the object causes a decrease in the measured mutualcapacitance between only some of the electrodes. For example, if afinger is placed near the intersection of transmit electrode 222 andreceive electrode 223, the presence of the finger will decrease thecharge coupled between electrodes 222 and 223. Thus, the location of thefinger on the touchpad can be determined by identifying the one or morereceive electrodes having a decrease in measured mutual capacitance inaddition to identifying the transmit electrode to which the TX signal224 was applied at the time the decrease in capacitance was measured onthe one or more receive electrodes.

By determining changes in the mutual capacitances associated with eachintersection of electrodes in the matrix 225, the presence and locationsof one or more conductive objects may be determined. The determinationmay be sequential, in parallel, or may occur more frequently at commonlyused electrodes.

In alternative embodiments, other methods for detecting the presence ofa finger or other conductive object may be used where the finger orconductive object causes an increase in measured capacitance at one ormore electrodes, which may be arranged in a grid or other pattern. Forexample, a finger placed near an electrode of a capacitive sensor mayintroduce an additional capacitance to ground that increases the totalcapacitance between the electrode and ground. The location of the fingercan be determined based on the locations of one or more electrodes atwhich a change in measured capacitance is detected, and the associatedmagnitude of capacitance change at each respective electrode.

The induced current signal 227 is integrated by demodulation circuit216. The rectified current output by demodulation circuit 216 can thenbe filtered and converted to a digital code by ADC 217.

A series of such digital codes measured from adjacent sensorintersections, when compared to or offset by the associated codes ofthese same sensors in an un-touched state, may be converted to touchcoordinates indicating a position of an input on touch sense array 121by touch coordinate converter 218. The touch coordinates may then beused to detect gestures or perform other functions by the processinglogic 102.

FIG. 3 illustrates an embodiment of a capacitive touch-sensing system300 that includes a capacitive-sense array 320. Capacitive-sense array320 includes multiple row electrodes 331-340 and multiple columnelectrodes 341-348. The row and column electrodes 331-348 are connectedto a processing device 310, which may include the functionality ofcapacitance-sensing circuit 101, as illustrated in FIG. 2. In oneembodiment, the processing device 310 may perform mutual capacitancemeasurement scans of the capacitive-sense array 320 to measure a mutualcapacitance value associated with each of the intersections between arow electrode and a column electrode in the sense array 320. Themeasured capacitances may be further processed to determine centroidlocations of one or more contacts of conductive objects proximate to thecapacitive-sense array 320.

In one embodiment, the processing device 310 is connected to a host 150which may receive the measured capacitances or calculated centroidlocations from the processing device 310.

The capacitive-sense array 320 illustrated in FIG. 3 includes electrodesarranged to create a pattern of interconnected diamond shapes.Specifically, the electrodes 331-348 of sense array 320 form a singlesolid diamond (SSD) pattern. In one embodiment, each intersectionbetween a row electrode and a column electrode defines a unit cell. Eachpoint within the unit cell is closer to the associated intersection thanto any other intersection. For example, unit cell 350 contains thepoints that are closest to the intersection between row electrode 334and column electrode 346.

In one embodiment, a capacitive touch-sensing system may collect datafrom the entire touch-sensing surface by performing a scan to measurecapacitances of the unit cells that comprise the touch-sensing surface,then process the data serially or in parallel with a subsequent scan.For example, one system that processes data serially may collect rawcapacitance data from each unit cell of the entire touch-sensingsurface, and filter the raw data. Based on the filtered raw data, thesystem may determine local maxima (corresponding to local maximumchanges in capacitance) to calculate positions of fingers or otherconductive objects, then perform post processing of the resolvedpositions to report locations of the conductive objects, or to performother functions such as motion tracking or gesture recognition.

In one embodiment, a touch-sensing system may be configured to performone or both of self-capacitance sensing and mutual capacitance sensing.One embodiment of a capacitive touch-sensing system that is configuredto perform self-capacitance sensing may, in sequence or in parallel,measure the self-capacitance of each row and column electrode of thetouch-sensing surface, such that the total number of sense operations isN+M, for a capacitive-sense array having N rows and M columns. In oneembodiment, the touch-sensing system may be capable of connectingindividual electrodes together to be sensed in parallel with a singleoperation. For example, multiple row and or column electrodes may becoupled together and sensed in a single operation to determine whether aconductive object is touching or near the touch-sensing surface. In analternate embodiment, the touch-sensing system may be capable ofconnecting each row electrode to it is own sensing circuit such that allrow electrodes may be sensed in parallel with a single operation. Thetouch-sensing system may also be capable of connecting each columnelectrode to its own sensing circuit such that all column electrodes maybe sensed in parallel with a single operation. The touch-sensing systemmay also be capable of connecting all row and column electrodes to theirown sensing circuits, such that all row and column electrodes may besensed in parallel with a single operation.

In one embodiment, a touch-sensing system may perform mutual capacitancesensing of the touch-sensing surface by individually sensing eachintersection between a row electrode and a column electrode. Thus, atotal number of sense operations for a capacitive-sense array having Xrows and Y columns is X x Y. In one embodiment, performing a mutualcapacitance measurement of a unit cell formed at the intersection of arow electrode and a column electrode includes applying a signal (TX) toone electrode and measuring characteristics of the signal on anotherelectrode resulting from the capacitive coupling between the electrodes.

In one embodiment, multiple capacitance sensing circuits may be used inparallel to measure a signal coupled to multiple column electrodessimultaneously, from a signal applied to one or more row electrodes. Inone embodiment, for a capacitive-sense array having X rows, Y columns,and N columns that can be sensed simultaneously, the number of mutualcapacitance sensing operations is the smallest whole number greater thanor equal to X×Y/N.

In one embodiment, each update of the touch locations may include asensing portion and a non-sensing portion. The sensing portion mayinclude measurement of capacitance associated with intersections betweenelectrodes, while the non-sensing portion may include calculation oftouch locations based on the capacitance measurements and reporting ofthe calculated touch locations to a host device.

Spatial accuracy of a passive stylus with existing sensor cells (alsoreferred to as a unit cell or intersection of a pair of electrodes) islimited because of low signals in the sensor cell under the passivestylus (cells i−1, i and i+1). Because of low sensitivity, it ischallenging to use a passive stylus for hand writing in a small screenon a device, such as a 10×15 mm box on a screen.

Good positional accuracy of the stylus' reported position is needed forhandwriting recognition by the sense array. Some handwriting requiresthat there be no more than 0.5 mm positional error in the presence ofnoise. The two-dimensional (2D) measurement method is very helpful tocombat the charger noise, but it can be used only with sensor cellswhich have symmetric capacitances Cf-rx and Cf-tx.

Achieving good accuracy is challenging when the sensor pitch is widerthan the stylus tip. FIG. 4 illustrates an embodiment of acapacitive-sense array 400 having a double solid diamond (DSD) pattern.The DSD sensor cells of the DSD pattern may have a sensor pitch of 4 mm.This sensor cell features electrodes built of diamond shape senseelements. Typically, row electrodes 402 in one direction are linked withindium tin oxide (ITO) necks in the same layer, while column electrodes404 are linked by bridges (jumpers). When a typical stylus (e.g., 2 mmstylus) is moved above the sensor unit cell in the x direction, itproduces the signal profile shown in FIG. 5.

FIG. 5 illustrates a cross section view of three unit cells andcorresponding capacitance profiles of the capacitive-sense array of FIG.4 according to one embodiment. When a stylus tip 501 moves over thethree unit cells 506 in the x direction 513, the unit cells 506 producea signal profile 508. A maximum signal is observed when the stylus 501is above a center of the unit cell 506. The signal descends fast whilestylus 501 is moved away from the center of the electrode. When thesignal strength falls below a noise level 505, these signals cannot beused for position calculation. When there are not enough signals forcentroid algorithm, such as when there are less than three signals, theposition of the stylus 510 cannot be calculated. It is said that thereis a “dead zone” on the unit cell. The sensor width of the unit cells(width of the electrode plus a gap between the adjacent electrode) isequal or less than a sensor pitch 503 of the sense array. The sensorpitch 503 can be measured between a center of one unit cell and a centerof an adjacent unit cell. Instead of being measured from centers of unitcells, the sensor pitch 503 can also be measured from one edge of anelectrode to the same edge of the adjacent electrode to include thewidth of the electrode and the gap between the electrodes.

The embodiments described herein are directed to unit cells that includeinterleaving sense elements. An electrode can be made up of tessellatedsense elements having different shapes, such as rows and columns ofsolid diamond sense elements. The sense elements are coupled together inrows or columns (e.g., single solid diamond (SSD) pattern) or inmultiple rows and multiple columns (e.g., double solid diamond (DSD)pattern). In the embodiments described herein, one or more of the senseelements are interleaving elements that interleave portions of otherelectrodes. For example, a column electrode may include some diamondshape sense elements and some interleaving sense elements thatinterleave with other interleaving sense elements of an adjacent columnelectrode, as illustrated in FIG. 7. As illustrated in FIG. 7, thediamond sense elements alternate with the interleaving sense elements.

In another embodiment, a capacitive-sense array includes a firstelectrode and a second electrode disposed adjacent to the firstelectrode in a first axis. The first electrode includes a first senseelement comprising a first shape and a first interleaving sense elementthat interleaves with a first portion and a second portion of the secondelectrode to extend a first dimension (width or height) of the firstelectrode to be greater than a sensor pitch in the first axis. The firstsense element and the first interleaving sense element have the samesurface area. In another embodiment, an area defined by a maximum widthof the first electrode and a maximum of height of the first electrode isat least two times a product of the first dimension and the seconddimension. The first interleaving sense element may include a baseportion and an extended portion coupled to the base portion via aconnecting line. The extended portion can be disposed to interleave withthe other portions of the second electrode. The surface area of the baseportion and extended portion has the same surface area as the firstsense element. In some embodiments, the shapes of the base portion andextended portion are such that they would form the same shape as thefirst sense electrode if connected. For example, as illustrated in FIG.7, the extended portion is a diamond shape and the base portion has anL-shape or a reverse L-shape and the connecting line couples the diamondshape and the L-shape or reverse L-shape.

In a further embodiment, the sense array includes the second electrodethat includes a second sense element with the same shape as the firstsense element and a second interleaving sense element that interleaveswith a first portion and a second portion of the first interleavingsense element to extend a second dimension of the second electrode to begreater than the sensor pitch in the first axis. The second dimensionmay be greater than the sensor pitch in the first axis by two or more.In further embodiments, the first electrode includes two columns or tworows of first sense elements and first interleaving sense elements. Thefirst electrode and the second electrode may be part of a first set ofelectrodes that are disposed in a first axis and a second set ofelectrodes are disposed in a second axis. One of the second set ofelectrodes can include a third sense element and a third interleavingsense element that interleaves with a first portion and a second portionof another one of the second set to extend a third dimension of oneelectrode to be greater than a second sensor pitch of the sense array inthe second axis. The second sensor pitch can be the same or differentthan the sensor pitch in the first axis. The third dimension may begreater than the sensor pitch in the second axis by two or more. Thefirst set of electrodes and the second set of electrodes can be disposedto form multiple unit cells each corresponding to an intersection of apair of electrodes including one electrode from the first set and oneelectrode from the second set.

In one embodiment, the first set of electrodes is a modified DSD patternincluding a first line of interconnected electrodes including firstdiamond shape elements and first interleaving elements that interleavewith portions of the second electrode on a first side and a second lineof interconnected electrodes including second diamond shape elements andsecond interleaving elements that interleave with portions of a thirdelectrode on a second side, as illustrated in FIG. 7.

In another embodiment, the first electrode and the second electrode arepart of a first set of electrodes in the first axis and a second set ofelectrode disposed in the second axis. In some embodiments, the firstset of electrode and the second set of electrodes are disposed in asingle layer, such as illustrated in the embodiments of FIGS. 10-13.FIG. 10 illustrates various embodiments of the first and second sets ofelectrodes form a swirl region used for interleaving in the singlelayer. For example, the swirl region can be a square swirl region, atriangle swirl region, a sector swirl region, or the like.

The embodiments described herein can provide an improved touchscreen byimproving sensitivity of measurements for sensing touch objects and byproviding better positional accuracy, especially for styli. Theembodiments described herein can enable a touchscreen of a device, suchas a tablet, to operate precisely with a passive stylus, as well ascontinue to operate with fingers or other conductive objects. Theembodiments describe herein can be more stylus-friendly than regularsensor arrays, allowing positions of the stylus to be determined withgreater accuracy. The interleaving sense elements turn the electrodesinto interleaved electrodes that have a greater dimension (width orheight) than the sensor pitch. The embodiments described herein canpermit detecting positions of narrow touch objects. For example, anarrow touch object may be a 1.7 mm stylus or a 2 mm stylus and aregular touch object may be 7 mm or larger.

FIG. 6 illustrates a cross section view of three unit cells andcorresponding capacitance profiles of the capacitive-sense array withinterleaving sense elements according to one embodiment. When a stylustip 601 moves over the three unit cells 606 in the x direction 613, theunit cells 606 produce a signal profile 608. A maximum signal isobserved when the stylus 601 is above a center of the unit cell 606. Thecapacitive-sense array with interleaving sense elements of FIG. 6 makesthe signal profile 608 wider (e.g., dCm profile). Unlike the signalprofile 508, the signal profile 608 does not descend as fast while thestylus 601 is moved away from the center of the electrode. Theinterleaved electrodes are physically wider than the sensor pitch 603 ofthe capacitive-sense array. In particular, a unit cell can have a width607 that is greater than the sensor pitch 603. In some embodiments, thewidth 607 is greater than the sensor pitch 603 by two or more times. Dueto wider electrodes, the stylus 601 can be sensed at wider span in thatdimension (e.g., x coordinate). As a result, the signal profile 608 (dCmprofile) is wider comparing to signal profile 508 (dCm profile) in theregular unit cell in FIG. 5. Provided the same sensor pitch, widersignal profile (dCm profiles) from the adjacent electrodes Rx1 and Rx3are crossing at higher point than they do in FIG. 5. As a result, allthree signals are above the noise level 605 at the point of crossing ofthe signal (dCm) from Rx2 with the signals (dCm) from Rx1 and Rx3. Thesensor cell of FIG. 6 does not have a dead zone at this noise level 605.As described above, sensor pitch 603 can be measured between a center ofone unit cell and a center of an adjacent unit cell. Instead of beingmeasured from centers of unit cells, the sensor pitch 603 can also bemeasured from one edge of an electrode to the same edge of the adjacentelectrode to include the width of the electrode and the gap between theelectrodes. However, as illustrated graphically in FIG. 6, theelectrodes have interleaving sense elements that interleave withportions of adjacent electrodes to create an electrode that is widerthan the sensor pitch 603.

The embodiments described below are directed to various patterns ofinterleaving electrodes.

FIG. 7 illustrates an embodiment of a capacitive-sense array 700 havinga DSD pattern with interleaving sense elements 701 according to oneembodiment. The depicted capacitive-sense array 700 includes two rowelectrodes 702 and two column electrodes. FIG. 7 illustrates a singlecolumn electrode 704 in the top-left view, two column electrodes 704 inthe top-right view, two row electrodes 702 in the bottom-left view, andthe combined capacitive-sense array 700 of the two column electrodes 704and two row electrodes 702 in the bottom-right view. Each electrode, asillustrated in the top left view of the column electrode 702, includestwo lines of tessellated sense elements. The tessellated sense elementsinclude alternating diamond sense elements 703 and interleaving senseelement 705. Each interleaving sense element 705 includes a base portion707 and an extended portion 709 coupled to the base portion 707 via aconnecting line 708. In this embodiment, the extended portion 709 has asmaller diamond shape than the diamond shape of the diamond senseelements 703. The extended portion 709 is disposed to interleave withthe extended portion 709 of an adjacent electrode, as illustrated in thetop right view of the two column electrodes 704. The interleaving senseelements 705 from adjacent electrodes form an interleaving region 711.The interleaving region 711 can be considered a swirl region, asdescribed herein. The interleaving region 711 of the capacitive-sensearray 700 can permit the row electrodes 702 to be disposed in a singlelayer with the column electrodes 704 without any additional bridges orjumpers. The capacitive-sense array 700 can be used for 2D sensingmethods. The intersections of the row electrodes 702 and the columnelectrodes 704 define unit cells 730. Each point within the unit cell730 is closer to the associated intersection than to any otherintersection. The unit cell 730 is a functional unit cell where acapacitance between a pair of electrodes can be measured and representedas a digital value. The electrodes can also be considered geometric unitcells in which the geometric unit cell is a unit of a repeatable patternor tessellations.

In this embodiment, the capacitive-sense array 700 has a pitch 713 in ay-axis and a pitch 715 in an x-axis. The pitches 713 and 715 may be thesame pitch or different pitches. The electrodes have a width 717, asillustrated in the column electrode 704. The width 717 is greater thanthe pitch 715. In other embodiments, other dimensions of the electrodescan be used than widths, such as heights. For example, the row electrode702 can have a height (not labeled) that is greater than the pitch 713.In one embodiment, the pitch 715 is 4 mm. Alternatively, otherdimensions may be used. The extended portion 709 has a dimension a 719(labeled a. Dimension 719 can be various sizes between 0.05 mm to 0.95mm for the pitch 715 of 4 mm. In one embodiment, the dimension 719 is0.75 mm.

In this embodiment, the capacitive-sense array 700 is a modified DSDpattern in which interleaving sense elements (e.g., extended portions709) penetrate adjacent electrodes. Shapes can be made in base portions707 of the adjacent electrodes to interleave with the extended portions709. In this embodiment, every other one of the diamond sense elementsis formed into interleaving sense elements. In other embodiments, otheralternating schemes or non-alternating schemes may be used for theinterleaving sense elements. In the depicted embodiment, the rowelectrodes 702 and the column electrodes 704 are identical, but disposedon two different axes. In other embodiments, the row electrodes 702 andthe column electrodes 704 may differ in shape and size from one another.

Signal profile curves for the unit cells for the DSD array 400 of FIG. 4and the interleaved DSD array 700 are compared in FIGS. 8-9.

FIG. 8 is a waveform diagram illustrating a signal response of thecapacitive-sense array of FIG. 4 according to one embodiment. FIG. 9 isa waveform diagram illustrating a signal response of thecapacitive-sense array of FIG. 7 according to one embodiment. For thesimulations of FIGS. 8-9, a 1.7 mm stylus was used on a 4 mm pitchsensor cell is used with 0.7 mm cover glass, and the short side, a, ofthe extended portion 709 in FIG. 9 is 0.75 mm. The graph 800 illustratessimulation results of three unit cells of the DSD array 400 to get amutual capacitance profile (dCm profile) with no “negative slope”. Thegraph 800 shows the dCm profiles for 1.7 mm stylus moved from the cellRx1 to the cell Rx3. The dCm profiles in FIG. 8 can be compared to dCmprofiles in graph 900 for the interleaved DSD array 700. The graph 900illustrates simulation results of three unit cells of the interleavedDSD array 700 to get a mutual capacitance profile (dCm profile) with no“negative slope”. The graph 900 shows the dCm profiles for 1.7 mm stylusmoved from the cell Rx1 to the cell Rx3.

It can be observed that for DSD array 400 in FIG. 8, the signal profilesRx1 and Rx3 are crossing at near zero value 801 (approximately at 0.0015pF). If the equivalent noise in the system is above 0.0015 pF, thecoordinate will not be possible to calculate. On other hand, as can beobserved in FIG. 9, the interleaved DSD array, the signal profiles Rx1and Rx3 are crossing at a higher value 901 (approximately 0.007 pFlevel). Thus, the signal in the side lobes is improved 4 times (from0.0015 to 0.007 pF,) which is equivalent to 4 times signal-to-noise(SNR) improvement. The embodiments have been shown be able to measure a2 mm stylus with the interleaved DSD array and compute a position with acentroid algorithm with a positional error of 0.67 mm, which is lowerthan 0.82 mm for 2 mm stylus being measured with the DSD array.

Embodiments of interleaved electrodes can be easily implemented in thetouchscreens where DSD, SSD and totem pole (TP) patterns are used. Asdescribed herein, various patterns can be used for interleaving senseelements to form the interleaving region, as referred to as a swirlregion. FIG. 10A illustrates a square swirl region 1002 according to oneembodiment. In FIG. 10A, interleaving is done by rectangular shapes andlinking traces that are arranged as a “swirl”. Other interlacing shapesare possible, for instance in FIGS. 10B-10C are shown triangular andsector shapes. FIG. 10B illustrates a triangle swirl region 1004according to one embodiment. FIG. 10C illustrates a sector swirl region1006 according to one embodiment. The swirl regions can be used forinterleaving electrodes in a single layer. The swirl regions can becounterclockwise swirls or clockwise swirls. Pattern with swirls can bederived from DSD, SSD or from other patterns. Examples of alternativeembodiments are shown in FIGS. 11A-11B and 12.

FIG. 11A illustrates a triangle swirl electrode 1100 used in aninterleaving DSD pattern according to one embodiment. In thisembodiment, the interleaving sense element has an extended portion,which is a portion of the diamond shape, and the extended portion isinverted and connected to the base portion by a connecting line.

FIG. 11B illustrates triangle swirl electrodes combined in aninterleaving DSD pattern 1150 according to one embodiment. FIG. 11B alsoillustrates a unit cell 1152 (an intersection between triangle swirlelectrodes.

FIG. 12A illustrates a swirl electrode 1200 used in an interleaving DSDpattern according to one embodiment. The swirl electrode 1200 is similarto the electrode 1100 with widened linking traces (parameter t).

FIG. 12B illustrates an embroidered swirl electrodes used in aninterleaving DSD pattern according to one embodiment. In thisembodiment, there are very wide linking traces.

FIG. 13 illustrates a sector swirl electrodes used in an interleavingSSD pattern 1300 according to one embodiment. In one embodiment, thesector swirl region can be used for SSD. The radius may be 1 mm and thet parameter may equal the s parameter, and they are both 0.05 mm.Alternatively, other dimensions may be used.

Rectangular, triangular and sector shapes were considered in Figuresabove. These shapes can be slightly modified, for instance, to pentagonor octagon shapes with performance remaining good enough. Also,extensions of electrodes can be made with curved boundaries.

Capacitive-sense arrays, in general, can be used for sensing metalobjects in industry. This solution can improve sensitivity ofmeasurement in industrial and biomedical applications.

Noise suppression with 2D measurement method with the embodiments of thepatterns describe herein can be as good as in the case with the DSDarray of FIG. 5.

FIG. 14 is a flow diagram of a method 1400 of sensing a capacitive-sensearray with interleaving sense electrodes according to an embodiment. Themethod 1400 may be performed by processing logic that may includehardware (circuitry, dedicated logic, etc.), software (such as is run ona general purpose computing system or a dedicated machine), firmware(embedded software), or any combination thereof. In one embodiment, theprocessing device 110 of FIG. 1 performs some or all of method 1400. Inanother embodiment, the processing logic 102 of FIG. 1 or FIG. 2performs some or all of the operations of method 1400. In otherembodiments, the capacitance-sensing circuit 101 performs some of theoperations of method 1400. Alternatively, other components of theelectronic system 100 of FIG. 1 perform some or all of the operations ofmethod 1400.

In FIG. 14, method 1400 begins with the processing logic applying atransmit (TX) signal on a first electrode of a first set of electrodesof a capacitive-sense array including a sensor pitch in a first axis(block 1402). The processing logic measures a receive (RX) signal on asecond interleaving electrode of a second set of electrodes (block1404). The first set of electrodes intersect the second set ofelectrodes to form unit cells each corresponding to an intersection of apair of electrodes comprising one electrode from the first set and oneelectrode from the second set. The second interleaving electrodeincludes a first sense element comprising a first shape and a firstinterleaving sense element. The first interleaving sense element isdisposed to interleave with a first portion and a second portion of athird electrode of the second set of electrodes. The first interleavingsense element extends a first dimension of the second electrode to begreater than the sensor pitch in the first axis. The processing logicconverts the measured RX signal into a first digital value (block 1406).The first digital value represents a first capacitance at theintersection between the first electrode and the second electrode.

In a further embodiment, the processing logic measures a second RXsignal on the third electrode of the second set of electrodes. The thirdelectrode includes a second sense element comprising the first shape anda second interleaving sense element. The second interleaving senseelement interleaves with a first portion and a second portion of thefirst interleaving sense element to extend a second dimension of thethird electrode to be greater than the sensor pitch in the first axis.The processing logic converts the second RX signal into a second digitalvalue. The second digital value represents a second capacitance at theintersection between the first electrode and the third electrode.

In a further embodiment, the processing logic applies the TX signal on afourth electrode of the first set of electrodes and measures a third RXsignal on the second electrode. The processing logic converts the thirdRX signal into a third digital value. The third digital value representsa third capacitance at the intersection between the fourth electrode andthe second electrode. The processing logic measures a fourth RX signalon the third electrode and converts the fourth RX signal into a fourthdigital value. The fourth digital value represents a fourth capacitanceat the intersection between the fourth electrode and the thirdelectrode.

The method may also include scanning other interleaving electrodes asdescribed above with respect to FIGS. 6-13.

The processing logic can be implemented in a capacitive touch screencontroller. In one embodiment, the capacitive touch screen controller isthe TrueTouch® capacitive touchscreen controllers, such as theCY8CTMA3xx family of TrueTouch® Multi-Touch All-Points touchscreencontrollers, developed by Cypress Semiconductor Corporation of San Jose,Calif. The TrueTouch® capacitive touchscreen controllers sensingtechnology to resolve touch locations of multiple fingers and a styluson the touch-screens, supports leading operating systems, and isoptimized for low-power multi-touch gesture and all-point touchscreenfunctionality. Alternatively, the touch position calculation featuresmay be implemented in other touchscreen controllers, or other touchcontrollers of touch-sensing devices. In one embodiment, the touchposition calculation features may be implemented with other touchfiltering algorithms as would be appreciated by one of ordinary skill inthe art having the benefit of this disclosure.

The embodiments described herein may be used in various designs ofmutual-capacitance sensing arrays of the capacitance sensing system, orin self-capacitance sensing arrays. In one embodiment, the capacitancesensing system detects multiple sense elements that are activated in thearray, and can analyze a signal pattern on the neighboring senseelements to separate noise from actual signal. The embodiments describedherein are not tied to a particular capacitive sensing solution and canbe used as well with other sensing solutions, including optical sensingsolutions, as would be appreciated by one of ordinary skill in the arthaving the benefit of this disclosure.

In the above description, numerous details are set forth. It will beapparent, however, to one of ordinary skill in the art having thebenefit of this disclosure, that embodiments of the present inventionmay be practiced without these specific details. In some instances,well-known structures and devices are shown in block diagram form,rather than in detail, in order to avoid obscuring the description.

Some portions of the detailed description are presented in terms ofalgorithms and symbolic representations of operations on data bitswithin a computer memory. These algorithmic descriptions andrepresentations are the means used by those skilled in the dataprocessing arts to most effectively convey the substance of their workto others skilled in the art. An algorithm is here and generally,conceived to be a self-consistent sequence of steps leading to a desiredresult. The steps are those requiring physical manipulations of physicalquantities. Usually, though not necessarily, these quantities take theform of electrical or magnetic signals capable of being stored,transferred, combined, compared and otherwise manipulated. It has provenconvenient at times, principally for reasons of common usage, to referto these signals as bits, values, elements, symbols, characters, terms,numbers or the like.

It should be borne in mind, however, that all of these and similar termsare to be associated with the appropriate physical quantities and aremerely convenient labels applied to these quantities. Unlessspecifically stated otherwise as apparent from the above discussion, itis appreciated that throughout the description, discussions utilizingterms such as “encrypting,” “decrypting,” “storing,” “providing,”“deriving,” “obtaining,” “receiving,” “authenticating,” “deleting,”“executing,” “requesting,” “communicating,” or the like, refer to theactions and processes of a computing system, or similar electroniccomputing device, that manipulates and transforms data represented asphysical (e.g., electronic) quantities within the computing system'sregisters and memories into other data similarly represented as physicalquantities within the computing system memories or registers or othersuch information storage, transmission or display devices.

The words “example” or “exemplary” are used herein to mean serving as anexample, instance or illustration. Any aspect or design described hereinas “example’ or “exemplary” is not necessarily to be construed aspreferred or advantageous over other aspects or designs. Rather, use ofthe words “example” or “exemplary” is intended to present concepts in aconcrete fashion. As used in this application, the term “or” is intendedto mean an inclusive “or” rather than an exclusive “or.” That is, unlessspecified otherwise, or clear from context, “X includes A or B” isintended to mean any of the natural inclusive permutations. That is, ifX includes A; X includes B; or X includes both A and B, then “X includesA or B” is satisfied under any of the foregoing instances. In addition,the articles “a” and “an” as used in this application and the appendedclaims should generally be construed to mean “one or more” unlessspecified otherwise or clear from context to be directed to a singularform. Moreover, use of the term “an embodiment” or “one embodiment” or“an implementation” or “one implementation” throughout is not intendedto mean the same embodiment or implementation unless described as such.

Embodiments descried herein may also relate to an apparatus forperforming the operations herein. This apparatus may be speciallyconstructed for the required purposes, or it may comprise ageneral-purpose computer selectively activated or reconfigured by acomputer program stored in the computer. Such a computer program may bestored in a non-transitory computer-readable storage medium, such as,but not limited to, any type of disk including floppy disks, opticaldisks, CD-ROMs and magnetic-optical disks, read-only memories (ROMs),random access memories (RAMs), EPROMs, EEPROMs, magnetic or opticalcards, flash memory, or any type of media suitable for storingelectronic instructions. The term “computer-readable storage medium”should be taken to include a single medium or multiple media (e.g., acentralized or distributed database and/or associated caches andservers) that store one or more sets of instructions. The term“computer-readable medium” shall also be taken to include any mediumthat is capable of storing, encoding or carrying a set of instructionsfor execution by the machine and that causes the machine to perform anyone or more of the methodologies of the present embodiments. The term“computer-readable storage medium” shall accordingly be taken toinclude, but not be limited to, solid-state memories, optical media,magnetic media, any medium that is capable of storing a set ofinstructions for execution by the machine and that causes the machine toperform any one or more of the methodologies of the present embodiments.

The algorithms and displays presented herein are not inherently relatedto any particular computer or other apparatus. Various general-purposesystems may be used with programs in accordance with the teachingsherein, or it may prove convenient to construct a more specializedapparatus to perform the required method steps. The required structurefor a variety of these systems will appear from the description below.In addition, the present embodiments are not described with reference toany particular programming language. It will be appreciated that avariety of programming languages may be used to implement the teachingsof the embodiments as described herein.

The above description sets forth numerous specific details such asexamples of specific systems, components, methods and so forth, in orderto provide a good understanding of several embodiments of the presentinvention. It will be apparent to one skilled in the art, however, thatat least some embodiments of the present invention may be practicedwithout these specific details. In other instances, well-knowncomponents or methods are not described in detail or are presented insimple block diagram format in order to avoid unnecessarily obscuringthe present invention. Thus, the specific details set forth above aremerely exemplary. Particular implementations may vary from theseexemplary details and still be contemplated to be within the scope ofthe present invention.

It is to be understood that the above description is intended to beillustrative and not restrictive. Many other embodiments will beapparent to those of skill in the art upon reading and understanding theabove description. The scope of the invention should, therefore, bedetermined with reference to the appended claims, along with the fullscope of equivalents to which such claims are entitled.

1-20. (canceled)
 21. A capacitive-sense array comprising a repeating pattern of conductive elements disposed along a first axis, wherein the repeating pattern comprises: a first conductive element comprising a first polygon shape with a first width defined along a second axis that is perpendicular to the first axis; a second conductive element that is electrically coupled to and co-planar with the first conductive element, wherein the second conductive element comprises a second polygon shape with a second width defined along a third axis that is perpendicular to the first axis and parallel to the second axis, wherein the second width is greater than the first width; a third conductive element that is electrically coupled to and co-planar with the second conductive element, wherein the third conductive element comprises the first polygon shape with the first width defined along a fourth axis that is perpendicular to the first axis and parallel to the second axis; and a fourth conductive element that is electrically coupled to and co-planar with the third conductive element, wherein the fourth conductive element comprises the second polygon shape with the second width defined along a fifth axis that is perpendicular to the first axis and parallel to the second axis.
 22. The capacitive-sense array of claim 21, further comprising a second repeating pattern of conductive elements disposed along a sixth axis that is parallel to the first axis, wherein the second repeating pattern comprises: a fifth conductive element comprising the first polygon shape with the first width; a sixth conductive element that is electrically coupled to and co-planar with the fifth conductive element, wherein the sixth conductive element comprises the second polygon shape with the second width; a seventh conductive element that is electrically coupled to and co-planar with the sixth conductive element, wherein the seventh conductive element comprises the first polygon shape with the first width; and an eighth conductive element that is electrically coupled to and co-planar with the seventh conductive element, wherein the eighth conductive element comprises the second polygon shape with the second width, and wherein the second repeating pattern is electrically coupled to the repeating pattern to form a first electrode.
 23. The capacitive-sense array of claim 22, further comprising a second electrode disposed along a seventh axis that is parallel to the first axis, wherein the second electrode comprises a third repeating pattern of conductive elements that interlock with the repeating pattern of conductive elements of the first electrode.
 24. The capacitive-sense array of claim 23, further comprising a third electrode disposed along an eighth axis that is parallel to the first axis, wherein the third electrode comprises a fourth repeating pattern of conductive elements that interlock with the second repeating pattern of conductive elements of the first electrode.
 25. The capacitive-sense array of claim 21, wherein the repeating pattern forms at least a portion of a first electrode, wherein the capacitive-sense array further comprises a second electrode disposed along a sixth axis that is parallel to the first axis, wherein the second electrode comprises a second repeating pattern of conductive elements that interlock with the repeating pattern of conductive elements of the first electrode.
 26. The capacitive-sense array of claim 21, further comprising a second repeating pattern of conductive elements disposed along a sixth axis that is parallel to the second axis, wherein the second repeating pattern comprises: a fifth conductive element comprising the first polygon shape with a third width defined along a seventh axis that is perpendicular to the sixth axis; a sixth conductive element that is electrically coupled to and co-planar with the fifth conductive element, wherein the sixth conductive element comprises the second polygon shape with a fourth width defined along an eighth axis that is parallel to the sixth axis and perpendicular to the seventh axis; a seventh conductive element that is electrically coupled to and co-planar with the sixth conductive element, wherein the seventh conductive element comprises the first polygon shape with the third width; and an eighth conductive element that is electrically coupled to and co-planar with the seventh conductive element, wherein the eighth conductive element comprises the second polygon shape with the fourth width.
 27. The capacitive-sense array of claim 26, wherein the repeating pattern forms at least a portion of a first electrode in a first coordinate axis of the capacitive-sense array and the second repeating pattern forms at least a portion of a second electrode in a second coordinate axis of the capacitive-sense array.
 28. The capacitive-sense array of claim 26, wherein the first width and the third width are the same, and wherein the second width and the fourth width are the same.
 29. The capacitive-sense array of claim 26, wherein the first polygon shape is a solid diamond, and wherein the second polygon shape comprises: a base portion; a connecting line; and an extended portion coupled to the base portion via the connecting line, wherein the extended portion comprises a second solid diamond that is smaller than the solid diamond of the first polygon shape.
 30. The capacitive-sense array of claim 22, wherein the capacitive-sense array comprises a sensor pitch defined by a sum of the first width and the third width, wherein a portion of the second conductive element is disposed to extend a first dimension of the first electrode to be greater than the sensor pitch in a first direction, and wherein a portion of the fourth conductive element is disposed to extend a second dimension of the first electrode to be greater than the sensor pitch in a second direction.
 31. The capacitive-sense array of claim 30, wherein an area defined by a maximum width of the first electrode and a maximum of height of the first electrode is at least two times a product of the first dimension and the second dimension.
 32. The capacitive-sense array of claim 32, wherein the first conductive element and the second conductive element comprise a same surface area.
 33. The capacitive-sense array of claim 23, wherein the first electrode and the second electrode are part of a first set of electrodes disposed in a first coordinate axis of the capacitive-sense array, and wherein the capacitive-sense array further comprises a second set of electrodes disposed in a second coordinate axis.
 34. The capacitive-sense array of claim 33, wherein the first set of electrodes intersect the second set of electrodes to form a plurality of unit cells each corresponding to an intersection of a pair of electrodes comprising one electrode from the first set and one electrode from the second set.
 35. A capacitive-sense array comprising: a first set of electrodes disposed in a first coordinate axis; a second set of electrodes disposed in a second coordinate axis that is orthogonal to the first coordinate axis, wherein the first set of electrodes intersect the second set of electrodes to form a plurality of unit cells each corresponding to an intersection of a pair of electrodes comprising one electrode from the first set and one electrode from the second set, wherein the first set of electrodes comprise a modified double solid diamond (DSD) pattern, wherein the modified DSD pattern comprises: a first line of interconnected electrodes comprising first diamond polygon shape elements and first interleaving elements that interleave with portions of the second electrode on a first side; and a second line of interconnected electrodes comprising second diamond polygon shape elements and second interleaving elements that interleave with portions of a third electrode on a second side.
 36. The capacitive-sense array of claim 35, wherein the first set of electrodes and the second set of electrodes are disposed in a single layer.
 37. An apparatus comprising: a capacitive-sense array of a plurality of electrodes, wherein the plurality of electrodes comprises: a first set of electrodes; and a second set of electrodes, wherein the first set of electrodes intersect the second set of electrodes to form a plurality of unit cells each corresponding to an intersection of a pair of electrodes comprising one electrode from the first set and one electrode from the second set, wherein a first electrode of the first set of electrodes comprises a repeating pattern of conductive elements disposed along a first axis, the repeating pattern comprising: a first conductive element comprising a first polygon shape with a first width defined along a second axis that is perpendicular to the first axis; a second conductive element that is electrically coupled to and co-planar with the first conductive element, wherein the second conductive element comprises a second polygon shape with a second width defined along a third axis that is perpendicular to the first axis and parallel to the second axis, wherein the second width is greater than the first width; a third conductive element that is electrically coupled to and co-planar with the second conductive element, wherein the third conductive element comprises the first polygon shape with the first width defined along a fourth axis that is perpendicular to the first axis and parallel to the second axis; and a fourth conductive element that is electrically coupled to and co-planar with the third conductive element, wherein the fourth conductive element comprises the second polygon shape with the second width defined along a fifth axis that is perpendicular to the first axis and parallel to the second axis; and a processing device coupled to the capacitive-sense array, wherein the processing device is configured to measure signals from the capacitive sense-array to determine capacitance values for the plurality of unit cells.
 38. The apparatus of claim 37, wherein the first polygon shape is a solid diamond, and wherein the second polygon shape comprises: a base portion; a connecting line; and an extended portion coupled to the base portion via the connecting line, wherein the extended portion comprises a second solid diamond that is smaller than the solid diamond of the first polygon shape.
 39. The apparatus of claim 37, wherein a second electrode of the first set of electrodes comprises a second repeating pattern of conductive elements disposed along a sixth axis that is parallel to the first axis, wherein the second repeating pattern comprises: a fifth conductive element comprising the first polygon shape with the first width; a sixth conductive element that is electrically coupled to and co-planar with the fifth conductive element, wherein the sixth conductive element comprises the second polygon shape with the second width; a seventh conductive element that is electrically coupled to and co-planar with the sixth conductive element, wherein the seventh conductive element comprises the first polygon shape with the first width; and an eighth conductive element that is electrically coupled to and co-planar with the seventh conductive element, wherein the eighth conductive element comprises the second polygon shape with the second width, and wherein the second repeating pattern is electrically coupled to the repeating pattern to form a first electrode.
 40. The apparatus of claim 37, wherein the first set of electrodes and the second set of electrodes are disposed in a single layer. 